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A Formal Object Model For Layered Networks To Support Verification And Simulation, Rasha M. B. E. Morsi Apr 2002

A Formal Object Model For Layered Networks To Support Verification And Simulation, Rasha M. B. E. Morsi

Electrical & Computer Engineering Theses & Dissertations

This work presents an abstract formal model of the interconnection structure of the Open Systems Interconnection Reference Model (OSI-RM) developed using Object-Oriented modeling principles permitting it to serve as a re-usable platform in supporting the development of simulations and formal methods applied to layered network protocols. A simulation of the object model using MODSIM III was developed and Prototype Verification System (PVS) was used to show the applicability of the object model to formal methods by formally specifying and verifying a Global Systems for Mobile communications (GSM) protocol. This application has proved to be successful in two aspects. The first …


Infopipes: An Abstraction For Multimedia Streaming, Andrew P. Black, Huang Jie, Rainer Koster, Jonathan Walpole, Calton Pu Apr 2002

Infopipes: An Abstraction For Multimedia Streaming, Andrew P. Black, Huang Jie, Rainer Koster, Jonathan Walpole, Calton Pu

Computer Science Faculty Publications and Presentations

To simplify the task of building distributed streaming applications, we propose a new abstraction for information flow – Infopipes. Infopipes make information flow primary, not an auxiliary mechanism that is hidden away. Systems are built by connecting predefined component Infopipes such as sources, sinks, buffers, filters, broadcasting pipes, and multiplexing pipes. The goal of Infopipes is not to hide communication, like an RPC system, but to reify it: to represent communication explicitly as objects that the program can interrogate and manipulate. Moreover, these objects represent communication in application-level terms, not in terms of network or process implementation.


Method For Preparing Porous Shells Or Gels From Glass Particles, D. E. Day, Samuel D. Conzone Mar 2002

Method For Preparing Porous Shells Or Gels From Glass Particles, D. E. Day, Samuel D. Conzone

Materials Science and Engineering Faculty Research & Creative Works

A method is provided for preparing shells, concentric shells or porous, homogenous gels from alkali borate glass particles at low temperatures (i.e. room temperature or less than above 100° C.). The alkali borate glass particles contain one or more cations such as aluminum which react with an aqueous solution containing an anion such as hydroxide to form an aqueous insoluble material having a solubility limit of less than about 0.01 wt. percent. TTie resulting shells or gels may be used in many different applications such as a filler in resins, as filters, precursors for nano-sized powders, as thin surface films …


Evaluation And Analysis Of Array Antennas For Passive Coherent Location (Pcl) Systems, Baris Calikoglu Mar 2002

Evaluation And Analysis Of Array Antennas For Passive Coherent Location (Pcl) Systems, Baris Calikoglu

Theses and Dissertations

Passive Coherent Location (PCL) systems use a special form of a radar receiver that exploits the ambient radiation in the environment to detect and track targets. Typical transmissions of opportunity that might be exploited include television and FM radiobroadcasts. PCL implies the use of a non-radar electromagnetic sources of illumination, such as commercial radio or television broadcasts also referred as transmitters of opportunity. The use of such illumination sources means that the receiver needs to process waveforms that are not designed for radar purposes. As a consequence, the receivers for PCL systems must be much more customized than traditional receivers, …


Kinetics Of Mn(Ii) Oxidation By Leptothrix Discophora Ss1, Jinghao Zhang, Leonard W. Lion, Yarrow M. Nelson, Michael L. Shuler, William C. Ghiorse Mar 2002

Kinetics Of Mn(Ii) Oxidation By Leptothrix Discophora Ss1, Jinghao Zhang, Leonard W. Lion, Yarrow M. Nelson, Michael L. Shuler, William C. Ghiorse

Civil and Environmental Engineering

The kinetics of Mn(II) oxidation by the bacterium Leptothrix discophora SS1 was investigated in this research. Cells were grown in a minimal mineral salts medium in which chemical speciation was well defined. Mn(II) oxidation was observed in a bioreactor under controlled conditions with pH, O>sub>2, and temperature regulation. Mn(II) oxidation experiments were performed at cell concentrations between 24 mg/L and 35 mg/L, over a pH range from 6 to 8.5, between temperatures of 10°C and 40°C, over a dissolved oxygen range of 0 to 8.05 mg/L, and with L. discophora SS1 cells that were grown in the presence …


Determination Of Chlorinated Solvent Contamination In An Upward Flow Constructed Wetland, Bryan C. Opperman Mar 2002

Determination Of Chlorinated Solvent Contamination In An Upward Flow Constructed Wetland, Bryan C. Opperman

Theses and Dissertations

The purpose of this study is to determine chlorinated solvent contamination levels in an upward flow constructed wetland at Wright-Patterson Air Force Base (WPAFB), Ohio. A stratified grid sampling methodology will be used in sampling the contaminated groundwater. Analysis will be accomplished by means of purge-and-trap gas chromatography. The contaminant concentration levels will be used to enhance the design and construction of man-made wetlands used to remove chlorinated solvents from aquifers. PCE levels declined from an average of 33.97 ppb in the inflow stream to an average of 3.65 ppb in the upper layer, a 91% reduction. High concentrations occurred …


An Analysis Of Horizontal Flow Treatment Well Applicability For The Treatment Of Chlorinated Solvent Contaminated Groundwater At United States Forces Korea Installations, Michael R. Staples Mar 2002

An Analysis Of Horizontal Flow Treatment Well Applicability For The Treatment Of Chlorinated Solvent Contaminated Groundwater At United States Forces Korea Installations, Michael R. Staples

Theses and Dissertations

Past research has shown that there is a rising public concern with environmental issues in the Republic of Korea (ROK). As Korean government and public interest in the environment grow, there is likely to be increased pressure to remediate environmental contamination at United States Department of Defense (DoD) installations in Korea. Impacting DoD's ability to remediate contaminated sites overseas is the fact that limited environmental funds must compete with high priority mission requirements. Thus, particularly at overseas bases, there is an urgent need for inexpensive and effective groundwater remediation technologies. Horizontal Flow Treatment Well (HFTW) systems have been demonstrated in …


The Management Of Energy Savings Performance Contracts (Espcs), Ericka M. Dailey Mar 2002

The Management Of Energy Savings Performance Contracts (Espcs), Ericka M. Dailey

Theses and Dissertations

Energy Savings Performance Contracts (ESPCs) originated to accomplish several objectives: (1) to meet energy efficiency goals mandated by executive orders and energy policies; (2) to improve federal government facilities using funds allocated for utility bills; and (3) to receive repayment of expenditures through energy savings reflected in reduced utility bills. In ESPC's, the contractor guarantees savings to the federal government agency. 10 CFR 436 limits the time necessary for payback. However, this regulation and others were written prior to the deregulation of utility companies. This theory is based on the underlying premise that the contractor payback is a direct result …


Groundwater Flow Through A Constructed Treatment Wetland, Andrew C. Entingh Mar 2002

Groundwater Flow Through A Constructed Treatment Wetland, Andrew C. Entingh

Theses and Dissertations

This study examines the flow of groundwater through one of the treatment cells. A major goal of the study is to determine whether the system design facilitates uniform vertical flows through the subsurface soil sediments or if preferential flows occur. Conceptually, uniform flows will achieve the most efficient degree of contaminant removal possible by evenly dispersing the groundwater contaminants throughout the full volume of the subsurface media. A three-dimensional grid of piezometers is used to generate potentiometric contour maps, and in-situ tests of hydraulic conductivity facilitate construction of a numerical computer model. The contours of hydraulic head, measured conductivities, and …


Efficient Modeling Of Discontinuities And Dispersive Media In Printed Transmission Lines, R. Araneo, Chen Wang, Xiaoxiong Gu, James L. Drewniak, S. Celozzi Mar 2002

Efficient Modeling Of Discontinuities And Dispersive Media In Printed Transmission Lines, R. Araneo, Chen Wang, Xiaoxiong Gu, James L. Drewniak, S. Celozzi

Electrical and Computer Engineering Faculty Research & Creative Works

The finite-difference time-domain method is applied to the analysis of transmission lines on printed circuit boards. The lossy, dispersive behavior of the dielectric substrate is accurately accounted for by means of several algorithms whose accuracy is discussed and compared. Numerical results are validated by comparisons with measurements and an equivalent circuit of slot in the ground plane is proposed.


A Stable Self-Tuning Fuzzy Logic Control System For Industrial Temperature Regulation, Zhiqiang Gao, Thomas A. Trautzsch, James G. Dawson Mar 2002

A Stable Self-Tuning Fuzzy Logic Control System For Industrial Temperature Regulation, Zhiqiang Gao, Thomas A. Trautzsch, James G. Dawson

Electrical and Computer Engineering Faculty Publications

A closed-loop control system incorporating fuzzy logic has been developed for a class of industrial temperature control problems. A unique fuzzy logic controller (FLC) structure with an efficient realization and a small rule base that can be easily implemented in existing industrial controllers was proposed. The potential of FLC in both software simulation and hardware test in an industrial setting was demonstrated. This includes compensating for thermo mass changes in the system, dealing with unknown and variable delays, operating at very different temperature set points without retuning, etc. It is achieved by implementing, in the FLC, a classical control strategy …


A Direct Sequence Code-Division Multiple-Access Local Area Network Model, James R. Rapallo Jr. Mar 2002

A Direct Sequence Code-Division Multiple-Access Local Area Network Model, James R. Rapallo Jr.

Theses and Dissertations

The United States Air Force relies heavily on computer networks for every-day operations. The medium access control (MAC) protocol currently used by most local area (LAN) permits a single station to access the network at a time (e.g. CSMA/CD or Ethernet). This limits network throughput to, at most, the maximum transmission rate of a single node with overhead neglected. Significant delays are observed when a LAN is overloaded by multiple users attempting to access the common medium. In CSMA/CD, collisions are detected and the data sent by the nodes involved are delayed and transmitted at a later time. The retransmission …


Evaluation And Mission-Specific Optimization Of Satellite Packet Telemetry Protocol For Use On Dod Flight Test Ranges, Beth A. Trapp Mar 2002

Evaluation And Mission-Specific Optimization Of Satellite Packet Telemetry Protocol For Use On Dod Flight Test Ranges, Beth A. Trapp

Theses and Dissertations

The DoD test range community has come to the realization that its telemetry abilities are obsolete. Efforts are therefore underway to improve telemetry systems at DoD test ranges. The overall objective of this project was to evaluate the practical use of the CCSDS packet telemetry protocol in DoD test ranges and determine the configuration that would maximize performance based on mission requirements. A secondary objective was to compare the CCSDS and ATM protocols in order to substantiate further exploration of using ATM in future DoD telemetry systems. Modeling and simulation of the CCSDS protocol showed a correlation between three CCSDS …


Modeling And Analysis Of Multicommodity Network Flows Via Goal Programming, Matthew A. Scott Mar 2002

Modeling And Analysis Of Multicommodity Network Flows Via Goal Programming, Matthew A. Scott

Theses and Dissertations

In this research we focused on the mobility system modeled by the AMC mobility planner's calculator (AMPCALC). We developed AMPCALC as a user-friendly tool and allow the user to easily carry out strategic airlift, air refueling and aeromedical evacuation calculations that are covered in Air Force Pamphlet 10-1403. In this study, Excel software and its macro language, Visual Basic for Application, are our two main tools. In the methodology of the thesis we examined fundamental aspects of the mobility system in AMPCALC. We discussed formulation logic of the mobility cycle. We presented ramp use optimization and tanker optimization processes. We …


Design And Fabrication Of Micro-Electro-Mechanical Structures For Tunable Micro-Optical Devices, Michael C. Harvey Mar 2002

Design And Fabrication Of Micro-Electro-Mechanical Structures For Tunable Micro-Optical Devices, Michael C. Harvey

Theses and Dissertations

Tunable micro-optical devices are expected to be vital for future military optical communication systems. In this research I seek to optimize the design of a microelectromechanical (MEM) structure integrated with a III-V semiconductor micro-optical device. The resonant frequency of an integrated optical device, consisting of a Fabry-Perot etalon or vertical cavity surface emitting laser (VCSEL), may be tuned by applying an actuation voltage to the MEM Flexure, thereby altering the device's optical cavity length. From my analysis I demonstrate tunable devices compatible with conventional silicon 5V integrated circuit technology. My design for a Fabry-Perot etalon has a theoretical tuning range …


Raman Spectroscopic Study On Mechanism Of Aluminum Triphosphate Pigment, Zhi-Jun Gu, Yong-Gui Liao, Zhi-Gang Zhang, Qi-Long Guo, Fang-Teng Su Feb 2002

Raman Spectroscopic Study On Mechanism Of Aluminum Triphosphate Pigment, Zhi-Jun Gu, Yong-Gui Liao, Zhi-Gang Zhang, Qi-Long Guo, Fang-Teng Su

Journal of Electrochemistry

The painted steel sample whose coating contained anticorrosive pigment has been investigated by Raman spectroscopy. The protective mechanism of aluminum triphosphate pigment for A3 steel is proposed as follows: Aluminum triphosphate can be dissolved and arrive at the surface of the steel.The dissolved triphosphate ions can complex with ferric ions.And the new products, namely ferric triphosphate, can strongly adhere at the surface of the steel by chemical bonds slowly. At last, a compact protective film, which effectively separates the steel substrate from the aggressive media, is formed at the steel surface.


Suggested Methodologies For Determining The Shgc Of Complex Fenestration Systems For Nfrc Ratings, Florida Solar Energy Center, Ross Mccluney Feb 2002

Suggested Methodologies For Determining The Shgc Of Complex Fenestration Systems For Nfrc Ratings, Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

Simple fenestration systems, for the purpose of this paper, are those whose solar heat gain and visible transmittance performances can be accurately simulated using the Window 4 or 5 programs developed at Lawrence Berkeley National Laboratory (LBNL). Complex fenestrations are everything else, including obscure or "privacy" glazing, corrugated or otherwise complex patterned glazing, curved, bent, or domed glazing, fritted glazing, glass blocks, glass fiber reinforced plastic daylighting panels, and glazings with internal or attached shading systems of a variety of types. The latter include exterior awnings and overhangs, attached exterior shade screens and shutters (including roll-up shutters), between-the-panes shades, including …


On The Use Of Linda As A Framework For Distributed Database Systems, Madhan M. Thirukonda, Ronaldo Menezes Feb 2002

On The Use Of Linda As A Framework For Distributed Database Systems, Madhan M. Thirukonda, Ronaldo Menezes

Electrical Engineering and Computer Science Faculty Publications

Linda is a coordination language capable of solving issues in distributed computing environments that relate to process synchronization, communication and creation. The expressiveness of Linda in distributed systems is such that researchers are proposing novel applications using Linda as a primary means of coordination. The examples range from peer-to-peer to groupware computing, from simple chat applications to control systems. Surprisingly, Linda has not been used in the field of distributed databases, although Linda can be helpful in solving coordination issues in a distributed database system. In this paper, we look at a possibility of using Linda in the context of …


Nanostructures With Small- And Large-Scale Periodic And Random Rough Surfaces And Lateral Fluctuations In The Permittivity And Permeability-Scattered Near Fields, Ezekiel Bahar Feb 2002

Nanostructures With Small- And Large-Scale Periodic And Random Rough Surfaces And Lateral Fluctuations In The Permittivity And Permeability-Scattered Near Fields, Ezekiel Bahar

Department of Electrical and Computer Engineering: Faculty Publications

The scattered electromagnetic near fields due to fluctuations in the surface height and/or lateral variations in the electromagnetic medium parameters are evaluated using a full-wave approach. Since the scales of the height and medium fluctuations considered could be significantly smaller or larger than the electromagnetic wavelengths, the familiar perturbation and physical/geometrical optics solutions cannot be used nor is it possible to investigate subwave length features based on far-field measurements. The full-wave approach employs complete field expansion that includes propagating and evanescent waves as well as lateral waves and surface waves, which are not accounted for in the perturbation and physical …


Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole Feb 2002

Hydrogen-Induced Embrittlement Of Candidate Target Materials For Applications In Spallation-Neutron-Target Systems, Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The purpose of this project is to evaluate the effect of hydrogen on cracking of candidate target materials for applications in spallation-neutron-target (SNT) systems such as accelerator production of tritium (APT) and accelerator transmutation of waste (ATW). The test materials will undergo appropriate thermal treatments prior to being hydrogen-charged by potentiostatic cathodic polarization technique in a simulated aqueous environment at different temperatures of interest. The specimens, upon completion of testing, will be metallographically examined. Further, the scanning electron microscopy (SEM) will be used to determine the extent and nature of cracking in the specimens tested. The thrust of the proposed …


Expression Of Active Human Factor Ix In Mammary Tissue And Of Milk Non Human Transgenic Mammals , William H. Velander, William N. Drohan Feb 2002

Expression Of Active Human Factor Ix In Mammary Tissue And Of Milk Non Human Transgenic Mammals , William H. Velander, William N. Drohan

Papers in Biotechnology

Recombinant Factor IX characterized by a high percentage of active protein can be obtained in the milk of transgenic animals that incorporate chimeric DNA molecules according to the present invention. Transgenic animals of the present invention are produced by introducing into developing embryos DNA that encodes Factor IX, such that the foreign DNA is stably incorporated in the DNA of germ line cells of the mature animal. Particularly efficient expression was accomplished using a chimeric construct comprising a mammary gland specific promoter, Factor IX cDNA that lacked the complete or any portion of the 5'-untranslated and 3'-untranslated region, which is …


Evaluation Of 220 Mhz Frequencies For Its Experimentation, David Q. Hunsucker Feb 2002

Evaluation Of 220 Mhz Frequencies For Its Experimentation, David Q. Hunsucker

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet implemented a 220 MHz wireless communication system as part of the TRIMARC traffic management system. The purpose of this research effort was to evaluate the use of the 220 MHz system to transmit data collected at the roadside to an operations center to enable operators to make sound decisions regarding traffic flow within the greater metropolitan area of Louisville, Kentucky. The attributes of the 220 MHz communication system, relative to functional reliability and cost effectiveness of the system were evaluated to determine if further use of 220 MHz technology for ITS applications is warranted.

The performance …


Forces On Permeable Conductors In Magnetic Fields, Lee W. Casperson Feb 2002

Forces On Permeable Conductors In Magnetic Fields, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

It is often implied that the force density formula dF/dV = JXB is all that is required to calculate the force that would be experienced by any stationary current-carrying medium in a region of space containing a magnetic field. However, representations of this formula are not all compatible, and the methods of applying such formulas when the conductor or surrounding medium have permeabilities different from vacuum are not widely known. The simplest case that one might consider is that of a current-carrying wire in an otherwise uniform field. It appears that the experimental measurements corresponding to such a situation have …


Bs News Feb 2002

Bs News

Building Services Engineering

No abstract provided.


Elementary, Pressure Dependent Model For Combustion Of C1, C2 And Nitrogen Containing Hydrocarbons : Operation Of A Pilot Scale Incinerator And Model Comparison, Chad Sheng Jan 2002

Elementary, Pressure Dependent Model For Combustion Of C1, C2 And Nitrogen Containing Hydrocarbons : Operation Of A Pilot Scale Incinerator And Model Comparison, Chad Sheng

Dissertations

A 140000 BTU/hr pilot scale incinerator has been constructed, tested and run; and an online sampling train capable of taking in situ data has been established. The continuous on-line analytical instruments include a CO analyzer, an NO/NOx analyzer and an 02 analyzer. In addition, two gas chromatographs with flame ionization detector are used to determine CH4, C2H2 + C2H4 and total hydrocarbon concentrations. Typical operating conditions are at an average 02 concentration of 6 - 8 %. The NO concentration ranged from 100 - 200 ppm. Approximately I ppm of CH.4 is also present at steady state operations.

The kinetic …


Global Expression Profiling Of Acetate-Grown Escherichia Coli, Min-Kyu Oh, Lars Rohlin, Katy Kao, James Liao Jan 2002

Global Expression Profiling Of Acetate-Grown Escherichia Coli, Min-Kyu Oh, Lars Rohlin, Katy Kao, James Liao

Faculty Publications

This study characterized the transcript profile of Escherichia coli in acetate cultures using DNA microarray on glass slides. Glucose-grown cultures were used as a reference. At the 95% confidence level, 354 genes were up-regulated in acetate, while 370 genes were down-regulated compared with the glucose-grown culture. Generally, more metabolic genes were up-regulated in acetate than other gene groups, while genes involved in cell replication, transcription, and translation machinery tended to be down-regulated. It appears that E. coli commits more resources to metabolism at the expense of growth when cultured in the poor carbon source. The expression profile confirms many known …


Effective-Medium Theories For Predicting Hydrodynamic Transport Properties Of Bidisperse Suspensions, Ashok S. Sangani, Sangkyun Koo Jan 2002

Effective-Medium Theories For Predicting Hydrodynamic Transport Properties Of Bidisperse Suspensions, Ashok S. Sangani, Sangkyun Koo

Biomedical and Chemical Engineering - All Scholarship

Effective-medium theories for predicting conditionally averaged velocity field and hydrodynamic transport coefficients of monodisperse suspensions are extended to bidisperse suspensions. The predictions of the theory are shown to agree very well with the results of direct numerical simulations of bidisperse suspensions with hard-sphere configurations up to volume fractions at which phase separation in bidisperse hard-sphere systems are observed.


Fall/Winter 2002, 90.9 Wmpg Fm Jan 2002

Fall/Winter 2002, 90.9 Wmpg Fm

WMPG Program Guides

Newspaper format


Spring 2002, 90.9 Wmpg Fm Jan 2002

Spring 2002, 90.9 Wmpg Fm

WMPG Program Guides

Newspaper format


Efficacy Of Interactive Internet-Based Education In Structural Timber Design, Aaron B. Henson, Kenneth J. Fridley, David Pollock, C Jayne Brahler Jan 2002

Efficacy Of Interactive Internet-Based Education In Structural Timber Design, Aaron B. Henson, Kenneth J. Fridley, David Pollock, C Jayne Brahler

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

While traditional teaching methods (e.g., real-time, synchronous lectures) have proven effective for training future engineers, the Internet provides an avenue to reinforce the material and augment student learning, comprehension, and retention of material. This paper presents the integration and assessment of a library of interactive instructional modules specifically for a senior-level undergraduate elective course in civil engineering. An ongoing, comprehensive assessment process was implemented in the fall 1999 semester. The results of this quantitative assessment indicate that the use of well designed and pedagogically sound Internet-based supplemental modules provide students with a better understanding of course material. However, when Internet-based …